YK11 – Myostine

YK11 – Myostine is one of the most talked-about compounds in the Canadian SARMs space for a reason: this steroidal selective androgen receptor modulator is a functional myostatin inhibitor, engineered to drive myogenic differentiation more powerfully than DHT in laboratory models by switching on follistatin, the body’s own brake-release on muscle growth.¹ If your research program demands a high-interest anabolic reference standard, YK11 – Myostine Canada delivers a uniquely potent, well-characterized mechanism for study. It ships strictly for laboratory and educational use only, never for human consumption.

What Is YK11 – Myostine?

YK11 (research name “Myostine”) is a synthetic, steroidal compound built on a testosterone/DHT-like backbone with a distinctive 17-alpha structure. Although it is routinely grouped with SARMs Canada suppliers list alongside compounds like LGD-4033 – Ligandrol and RAD 140 – Testolone, YK11 is mechanistically distinct: it behaves as a partial-agonist selective androgen receptor modulator and, most notably, as an indirect functional myostatin inhibitor. Because there are no human clinical trials of YK11, every claim about its activity rests on preclinical cell-culture and rodent research. It is sold here purely as a research chemical and reference material for laboratory investigation, not as a supplement, drug, or product for human or veterinary use.

How YK11 Works

YK11 binds and activates the androgen receptor (AR), but it does so in a “gene-selective” way: it does not fully induce the N-terminal/C-terminal (NTD/AF1–LBD/AF2) interaction required for complete AR transactivation, which is what distinguishes it from conventional anabolic androgens. Its signature effect is achieved indirectly. In C2C12 myoblasts, YK11 up-regulates follistatin (an endogenous antagonist of myostatin), and this follistatin surge drives myogenic differentiation via induction of the myogenic regulatory factors MyoD, Myf5 and myogenin, more strongly than DHT.¹ An anti-follistatin antibody reverses the effect, which confirms that follistatin is central to YK11’s action.¹ Through the same AR-dependent pathway, YK11 has also been shown to promote osteoblast proliferation and mineralization.² Because AR antagonists attenuate these responses, the compound’s activity is understood to be androgen-receptor dependent.

What the Research Shows

• Follistatin-driven myogenesis. In C2C12 myoblasts, YK11 induced myogenic differentiation more potently than DHT by up-regulating follistatin; an anti-follistatin antibody reversed the effect, establishing a follistatin-mediated, myostatin-inhibitor-like anabolic mechanism operating through the androgen receptor.¹
• Osteogenic / bone activity. In MC3T3-E1 cells, YK11 (like DHT) accelerated osteoblast proliferation and mineralization and increased osteoprotegerin and osteocalcin; an androgen receptor antagonist blocked these effects, indicating AR-dependent anabolic bone activity.²
• Neurochemical caution flag. In rats, YK11 increased hippocampal oxidative stress, impaired the endogenous antioxidant system, and caused mitochondrial dysfunction and proteotoxicity; exercise did not fully reverse these impairments, flagging a potential neurological risk.³

Researchers comparing anabolic SARM reference standards often study YK11 alongside MK2866 – Ostarine and the growth-hormone secretagogue MK-677 – Ibutamoren to contrast receptor-selective and myostatin-linked mechanisms.

Chemical Properties

Research Protocols & Handling

YK11 – Myostine is provided exclusively as a research chemical for in-vitro and preclinical laboratory investigation and educational reference. It is not for human consumption and not for veterinary use. Handle it only in an appropriate laboratory setting using standard personal protective equipment. As a general guideline for steroidal research compounds, store the sealed material in a cool, dry, dark place; where a solution is required, many laboratories reconstitute or dissolve YK11 in a suitable organic vehicle (such as DMSO or ethanol) rather than water, aliquot to minimise freeze–thaw cycles, and store working solutions frozen and protected from light. Always confirm handling, solubility and stability parameters against your own institution’s protocols and the accompanying certificate of analysis.

Potential Side Effects & Safety

References

Peer-reviewed and authoritative sources cited above. Helixx supplies research materials for laboratory and educational use only; citations are provided for independent verification, not as medical guidance.

1. Kanno Y, Ota R, Someya K, Kusakabe T, Kato K, Inouye Y. Selective androgen receptor modulator, YK11, regulates myogenic differentiation of C2C12 myoblasts by follistatin expression. Biol Pharm Bull. 2013;36(9):1460-5. PMID: 23995658.
2. Yatsu T, Kusakabe T, Kato K, Inouye Y, Nemoto K, Kanno Y. Selective Androgen Receptor Modulator, YK11, Up-Regulates Osteoblastic Proliferation and Differentiation in MC3T3-E1 Cells. Biol Pharm Bull. 2018;41(3):394-398. PMID: 29491216.
3. Dahleh MMM, Bortolotto VC, Guerra GP, Boeira SP, Prigol M. YK11 induces oxidative stress and mitochondrial dysfunction in hippocampus: The interplay between a selective androgen receptor modulator (SARM) and exercise. J Steroid Biochem Mol Biol. 2023;233:106375. PMID: 37468001.